Herein the inventors demonstrated that CD4 and CD8 T cells from COVID-19 patients are more prone to undergo death and that blocking caspase activation prevents T cell death. Furthermore, they found that higher levels of soluble FasL in the plasma of COVID-19 individuals is associated with higher levels of T cell death. This propensity of CD4 T cells to die as well of FasL levels is associated with lower specific SARS-CoV-2 IgG response. The presence of higher levels of soluble caspase-1 in the plasma and of IL-18 also indicated an inflammasome activation pathway, which can be link with several endothelial biomarkers of cell damage. Therefore, strategy aims to block caspase and/or FasL could be beneficial for restoring full immune competent immune cells and preventing fatal outcome in COVID-19 patients.